Meteor, comet or asteroid?

With two prominent meteor showers coming this month, here's how to tell a meteor from an asteroid from a comet.

Meteoroid: A small rocky or metal object, usually between the size of a grain of sand or a boulder, that orbits the sun. It originates from a comet or asteroid.

Meteor: A meteoroid that enters the earth's atmosphere and vaporizes. Also called a "shooting star."

Meteorite: A meteor that hits earth without burning up in the atmosphere.

Meteor shower: A collection of meteors visible when earth passes through a trail of debris left by a comet.

Asteroid: An object larger than a meteoroid that orbits the sun and is made of rock or metal. Historically, objects larger than 10 meters across have been called asteroids; smaller than that they've been called meteoroids.

Comet: A body of ice, rock and dust that can be several miles in diameter and orbits the sun. Debris from comets is the source of many meteoroids.